Appeal 3320928

The appeal is allowed and planning permission is granted for a roof extension over the existing raised ground floor, with matching painted timber sash windows, stucco front elevation and stock brick rear and side elevations at [site address] , Kensington and Chelsea, London W10, in accordance with the terms of the application [name]/23/00025, dated 22 December 2022, subject to the following conditions:

The development hereby permitted shall begin not later than 3 years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the following approved plans: PD01.1, PD01.2, PD01.3, PD02, PD03 and PD04.

During construction of the development hereby permitted the sustainable drainage system set out in the report by [name] shall be fully implemented and maintained thereafter.

The windows in the development hereby permitted shall be timber framed, white painted, double hung sliding sashes with integral glazing bars and so maintained.

The main issue is the effect of the proposal on the character and appearance of the appeal dwelling and that of the local area, with reference to the [address] -St Quintin Conservation Area (the CA)

The appeal dwelling occupies a flat roofed two storey building attached to the side of a larger multi-unit substantial residential building. It appears as a set-back, plainly designed, subservient side element of this larger property, with a single storey entrance porch at lower ground floor level. The front is finished in white stucco with London stock brick to the side and rear elevations.

The appeal dwelling is in a tree lined street predominantly made up of substantial detached 19th Century residential properties. This is located within the CA, recognised as a heritage asset through its designation by the Council. [address] - St Quintin Conservation Area Appraisal (2021) (The CA Appraisal) sets out that the significance of which rests in its substantially unaltered good quality mid-Victorian and later residential architecture that provides for cohesive streetscapes.

In line with the duty imposed on me by section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990, I have given considerable importance and weight to the desirability of preserving or enhancing the character or appearance of the Conservation Area.

The proposed extension would result in a building a storey taller but of the same architectural expression as existing. This would be achieved by the proposed extension sitting entirely above the existing raised ground floor of the appeal dwelling, replicating its scale, external appearance and materials. The existing parapet detailing would also be replicated at the top of the proposed extension and removed from the top of the existing ground floor. A blue/green roof is also proposed to reduce rainwater runoff as part of a sustainable drainage system.

To present an evenly spaced and symmetrical window arrangement, the proposal also includes additional and realignment of windows in the rear upper ground floor elevation. This arrangement would also be replicated in the rear elevation of the proposed extension, resulting in the alignment of windows in the rear elevation as a whole. The proposal would also replicate the detailed design of the existing timber framed sash windows.

The proposal would be of a scale in relation to the appeal dwelling that that it would appear as a subservient addition, and the appeal dwelling would continue to appear to be subservient to the larger building to which it is attached. By replicating the design of the existing it also appears as a complimentary and harmonious addition. In combination, this results in the appeal dwelling appearing as complete and proportionate rather than as a squat and under scaled building, especially in relation to its attached neighbour and the rest of the substantial residential buildings in the street.

The CA Appraisal recognises that the gap in the skyline, between the building to which the appeal dwelling is attached and the neighbouring building, is a feature in the local streetscape of otherwise closely positioned substantial detached houses. Although the proposed extension infills some space above the appeal dwelling, it would not intrude into the skyline defined by the surrounding taller buildings. The proposal would also not reduce the side gap between the appeal dwelling and its nearest detached neighbour. As such, I find that, although the space above the existing building would be partially infilled, the gap in the skyline would be substantially retained and would retain the effect of this gap on the character and appearance of the local area and the significance of the CA.

Other interested parties have raised concerns with regard to the effect of the proposal on the living conditions of neighbouring residential occupiers, with reference to outlook and privacy and loss of light. Given the scale of the proposed development and distances involved, the proposal would not result in an additional degree of overlooking or impact on outlook or light, and reflects the relationship between buildings that is to be expected in a developed residential area of this type. I find, therefore, that the proposed development would not result in any significant harm to the living conditions of neighbouring residential occupiers.

For the reasons given above, I find that proposal would not result in any significant harm to the character and appearance of the appeal dwelling and that of the local area, leaving the significance of the CA preserved. This would accord with Policies CL1, CL2, CL3 and CL11 of The Royal Borough Kensington and Chelsea Local Plan (2019), which seek to ensure that development is architecturally sympathetic to the age and character of the host building, reinforces their original integrity, does not harm the character and appearance of the existing building, respects the existing views, is of high architectural and urban design quality and preserves or enhances the appearance and character of conservation areas. For these reasons the developments proposed would also not accord with Policies D3 and HC1 of the London Plan (2021) and sections 12 and 16 of the Framework.

I have had regard to the Council’s suggested conditions should I allow the appeal. I have not included the suggested pre-commencement condition regarding submission and approval of a Site Construction Management Plan, as the scale of the development does not justify such a condition and would be unnecessary. As such, there are no exceptional reasons for a pre-commencement condition and this suggested condition would not meet the requirements for conditions set out in the National Planning Policy Framework (2023).

Along with the standard condition of the timing of the development, I have, in the interests of design quality included conditions requiring compliance with approved drawings and white painted timber sash windows. To reduce flood risk, I have also attached a condition requiring implementation of a sustainable urban drainage system.

The appeal is allowed.